Bandsaw blades are designed with specific tooth pitch in order to be able to properly cut certain sized materials. These teeth are essential to achieving accurate cuts and positive output.
A complete set of teeth on an operational saw blade prevents chips from sticking to the blade and the materials being cut, offering the smooth, flawless finish everyone desires in their work.
Bandsaw blades are made with specific tooth designs and the purposes of that engineering helps in the following ways:
- Offering the ability to remove chips from the material being cut
- Efficiently carrying the chips out of the cut
A bandsaw’s teeth are being subjected to high forces, abrasion, heat, and corrosive chemicals in the material being cut. This may result in missing or stripped blade teeth.
There are a lot of factors that could lead to stripping and broken blade teeth. It is important to know these factors in order to avoid experiencing an unsuccessful cutting process.
As a bandsaw machine operator, consider that tooth pitch is an important factor leading up to stripped and broken teeth.
To help determine proper blade pitch, calculate the dimension of the material being cut and multiply that by the average TPI that you think might be used.
If cutting a 4″ solid round, and the blade is 4-6 TPI, then the average TPI is 5.
5 x 4 = 20, — which is pretty close to the maximum number of teeth desired in that particular cut.
As a professional bandsaw operator, make the decision to use a 4-6 TPI blade or drop down to a 3-5. If available from the manufacturer, the saw blade would have a 16TPI — closer to the optimum number of 12 TPI than a 5 TPI.
Other factors to consider about TPI are the number of pieces being cut at one time and the bandsaw design.
Here are just a few of the problems with improper use of TPI that will cause a bandsaw blade’s teeth to break or strip, and their solutions:
- Too few teeth in the cut — use a finer tooth pitch
- Too many teeth in the cut — use a coarser tooth pitch
- Excessive and inadequate feed rate causing over or under penetration — adjust the feed rate
- Chip brush not working correctly, chips are carried back into the cut — replace chip brush
- Crooked weld — make sure the saw blade is slightly hollow on the cutting edge
- Slipping saw blade — check and readjust the blade’s tension
- Improper break-in — follow the proper break-in procedure with any new blade
- Coolant problems — check the concentration, adjust the fluid flow, and add coolant nozzles if needed
- The material is too hard — review the feed and speed chart and adjust the cutting parameter as necessary
It is essential for an operator to know the basics in order to avoid stripping blade teeth.
If one tooth is stripped, another will soon follow. This will continue to occur until most all of the teeth are removed. Even with a single tooth missing, a stripped saw blade will give inaccurate cuts and produce an unsuccessful output.
Always use a quality saw blade that is appropriate for the materials being cut.